Electric car-brake



' (No Model.)

4C. R. ARNOLD. ELECTRIC GAR BRAKE.

No. 457,067. Patented Aug. 4, v1891.

ATTEST: INVENTUH:

UNITED STATES PATENT OifEICE.,v

CRAIG RITOHIE ARNOLD, OF SHARON l-IILL, PENNSYLVANIA.

ELECTRIC CAR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 457,067, dated August4, 1891. Application filed August 2l, 1890. Serial Nox 362,572. (Nomodel.)

.,way-car brakes in which the power of an electro magnet is employed fordrawing the brake-shoe against the wheel.

The object of my invention is to produce a brake of this character inwhich the power of the magnet shall be eficiently employed.

A further object of my invention is to simplify brakes of the generalcharacter in which the brake-shoe is drawn by the action of the magnetagainst the car-wheel.

My invention consists, essentially, in utilizing the car-Wheels to formparts of a closedl magnetic circuit from one pole to the other of thebrake-magnet, so as to constitute a part of a closed magneticcircuit-armature for the magnet.

My invention consists, further, in arailwaycar brake wherein thebrake-magnet has its magnetic circuit completed eXteriorly through twocar-wheels and a section of railway-rail between them.

My invention consists, further, in other details of construction, andcombinations of devices, more particularly hereinafter described, andthen specied in the claims.

The accompanying drawings show in side elevation and diagrammatically anorganization in which my invention is embodied.

C C indicate the wheels of a railway-car, and G the rail upon which theytravel.

A A2 indicate the brake-magnet, made either in one or two parts, butpreferably in two parts, which are pivoted upon an upright 10, risingfrom the car-truck. The parts A A2 are in such magnetic relation to oneanother that a practically continuous magnetic circuit exists from onepart to the other. The

I electro-magnet A A2 is wound with the usual coils of energizing-wire,(indicated in skeleton,) through which coils an electric current iscaused to iiow from any desired source when the brake is to be applied.The coils are wound so that the opposite terminals B to become virtuallythe polar extremities ofv the electro-magnet. lVhen the magnet is eX-cited, the brake-shoes are drawn down upon the wheels C C. Any suitablemeans, as springs, may be employed for holding the brake-shoes normallyoff the wheels. When the magnet is excited and the brake-shoes are drawndown upon the Wheels, the magnetic circuit is formed from one pole B ofthe electro-magnet to the other pole B2, through the two wheels C and asection of rail G between them. rlhe wheels O and the section of rail Gform an armature for the electro-magnet, thus permitting it to act withfull power in keeping the shoes D drawn against the wheel.

Magnetic polarities are formed in the mag netic circuit from one pole tothe other at the points indicated by the letters N S. Thus, asindicated, two opposite poles N S will exist, respectively, in the wheeland in the part of the rail upon which said wheel rests. The eifect ofthis is obviously to increase the friction between the wheel and therail, so that a greater power may be applied to the brake withoutcausing the wheel to slip.

I do not limit myself to any particular way of mounting the magnet, norto the making of the same in any particular number of pieces. I preferto construct it, however, in two parts hinged or jointed together, asshown, so that the magnet maybe in part supported by the truck insteadof Wholly by the retracting devices.

By my invention it will be seen that the two car-wheels themselves beingoppositely magnetized and being virtually the poles of a magnetconstituted by the car-wheels and the iron cores or masses of ironconnecting them at their top the section of rail between such wheelswill be a true armature joining two opposite poles of a magnet. Theadhesion between the car-wheels and the track is by this means so farincreased that the carwheels will be held down upon the track and beprevented from leaving' the same. This is a valuable feature, inasmuchas when the IOO brakes are applied in an emergency7 the adhesion betweenthe wheels and rails thus produced will tend not only to prevent thewheels from leaving the rails, but to prevent overturning of the truckand car. This feature of my invention, it will be observed, is`of valueindependently of the braking action produced by the magnetizedbrake-shoes.

Vhat I claim as my invention is- I. In a railway-brake, a brake-1n agnethaving brake shoes constituting the opposite poles of such magnet andbearing, respectively, upon two car-Wheels, said wheels with the sectionot' rail between them forming a closed magnetic circuit from one pole tothe other of the magnet.

2. In an electric railway-brake, an electromagnet made in two parts,pivoted in magnetic connection and arranged parallel with the rail, incombination with brake-shoes carried by and in magnetic connection withthe poles of such magnet and bearing, respectively, on different wheelsrunning on the same rail.

3. In a railway-brake, the combination, substantially as described, ofan electro-magnet made in two parts, pivoted on the car-truck andarranged to swing in a vertical plane, and brake-shoes attached to andforming a part of the pole ends of such magnet, which are Aof oppositepolarity, respectively, and

adapted to bear, respectively, on two car- Wheels at the same side ofthe truck, so that the magnetic circuit for said electro-magnet will becompleted through the car-wheels of opposite polarity and the section oftrack between them.

4. The combination, with two car-wheels running on the same rail, of anelectro-magnet bridging the space between said wheels and having itsopposite polar ends constituting brake-shoes arranged to polarize saidWheels respectively, as described, so that said wheels with the sectionof track between them shall form a closed magnetic circuit or armaturefrom one pole to the other of the magnet.

5. .The combination, With the car-wheels running on the same rail, of anelectro-magnet, the opposite polar ends of which polarize said wheels,as described, so that the wheels with the section of track between themshall form a closed magnetic circuit from one pole to the other of themagnet.

Signed at Chester, in the county of Dela; ware and State otPennsylvania, this 4th day of August, A. D. 1890.

CRAIG RiToHn: ARNOLD.

Witnesses:

LETTIE D. ALLMoND, Jos. H. HINKsoN.

